Wearable devices appear on the market only in recent years. They win the favor of the users soon, for they can be easily worn and support many functions, like shooting function and communication function etc.
In wearable devices currently on the market, a display body and a fixation unit thereof almost are relatively fixed, such structure causes inconvenience to the users in some aspects. For example, a display body and a strap of a smart watch are fixed, when a user desires to adjust the display body from the inside of the wrist to the outside thereof, he/she needs to rotate the strap to achieve this. However, the strap usually has a relatively large friction with the wrist, so it will take some time to adjust, and the user's wrist feels discomfort.
Therefore, in the wearable devices, the relative position between respective bodies is unchangeable.